The present invention is related to “smart antenna” systems. More particularly, the invention is directed to a “smart antenna” system for use in cellular networks where the wireless transmit/receive unit and/or the base station utilize multi-user detection (MUD).
A smart-antenna system generally refers to a composition of several transmit and/or receive antenna elements together with a signal processing protocol which utilizes these antennas to improve the quality of signal reception and the capacity of the cellular networks.
Smart antennas have been widely studied and have been shown to have high potential for performance improvement. A major drawback of most current smart antenna technologies, however, is the significant complexity required to provide more than a marginal improvement in performance. This problem is exacerbated in systems that also utilize multi-user detection (MUD) techniques. Further, current smart antenna techniques only maximize the received power at each WTRU and do not deal with interference to and from other users.